Copyright (c) 2007, 2018, Oracle and/or its affiliates. All rights reserved.

DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

This code is free software; you can redistribute it and/or modify it

under the terms of the GNU General Public License version 2 only, as

published by the Free Software Foundation.

This code is distributed in the hope that it will be useful, but WITHOUT

ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

version 2 for more details (a copy is included in the LICENSE file that

accompanied this code).

You should have received a copy of the GNU General Public License version

2 along with this work; if not, write to the Free Software Foundation,

Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

or visit www.oracle.com if you need additional information or have any

questions.

Test garbage collector compaction.

The test starts several threads which create objects using

given garbage producer until OOM. The references are kept

in an array. The references to even elements are cleared

and objects of double size are created until OOM. The garbage

collector will have to compact free space to free memory for

new objects.

The tests differ by object types used for first and second phase:

- _Arrays tests randomly use arrays of basic types and Object[] arrays.

- _Strings tests use random strings.

- _NonbranchyTree tests use nonbranchy trees.

- _InternedStrings use interned strings.

- _ArrayOf tests use array with two elements for second phase,

the elements of which point to objects of same type.

- _TwoFields tests use object with two fields for second phase,

which point to objects of same type.

Each *1 test is the single-threaded version of corresponding test.

The Humongous tests are similar to compact tests. However they used

the fixed size of objects which allocation requre compaction. The

size is specific for G1 GC (about 1M and 5M) and require humongous

object creation in G1.